Many pharmaceutical materials, such as, for example, insulin, are subject to rapid deterioration or degradation when exposed to ambient temperature conditions. This characteristic of the pharmaceutical materials makes it very difficult for persons required to regularly use such preparations to carry them on their person while maintaining them at a temperature sufficiently cool as to prevent degradation of the material. As an example, insulin is required to be maintained at a temperature of substantially below ambient temperature in order to avoid deterioration and degradation. Many persons who regularly use insulin require dosages two or three times a day. Those persons are required to transport this insulin supply with them whenever they are away from their refrigerated insulin supply for a period longer than three or four hours. Generally, such persons simply utilize a small cooler filled with ice to transport their insulin supply, but this is extremely difficult in many situations, as for example, when moving about on an all-day shopping trip or when on an all-day hike, etc.
In order to enable persons who regularly need cooled medication to transport a limited supply of that medication, it has been proposed to utilize small, portable carriers for transporting a limited supply of such medication. One such carrier is disclosed in Galloway, et al. U.S. Pat. No. 4,573,481. The carrier disclosed in this patent, though, while relatively small and portable, is one which is relatively expensive to manufacture and/or for a user to purchase because of its numerous plies of insulating material, heat sink material and heat reflective material.
A less expensive insulated container for transporting heat sensitive materials is disclosed in Heffler, et al. U.S. Pat. No. 3,309,893. This patent discloses an insulative container made from rigid polyurethane foam within which there is a central cavity. This cavity is closed by a lid of flexible polyurethane foam which fits tightly within and seals the cavity after placement of the heat-sensitive material within the cavity of the container. This container, though, is also excessively expensive for many applications.